Variable pitch propeller



April 15, 1952 H. GANSERT 2,593,290

VARIABLE PITCH PROPELLER Filed Dec. 20, 1950 2 SHEETS-SHEET 1 INVENTOR b'mnmv 'mvse'kr ATTORNEYS A ril 15, 1952 Filed Dec. 20, 1950 H. GANSERT VARIABLE PITCH PROPELLER 2 S!-1EETS-SHEET 2 ATTORNEYS I Patented Apr. 15, 1 952 UNITED STATES PATENT OFFICE VARIABLE PITCH PROPELLER Herman Gansert, Syracuse, N. Y.

Application December 20, 1950, Serial No. 201,741

This invention relates to accessories for a propeller driven machine and has specific reference to an improved device for varying and reversing the pitch angle of propellers used in connection with such machines.

Though the device of the present invention may be used with propellers on airplanes, aircraft of other types, and boats, it is principally designed for use with propellers on marine outboard motors. blades of a propeller may be quickly and conveniently adjusted to any angle best adapted to special conditions of use. It is also contemplated that the blades may be readily and conveniently shifted for propelling the vessel backward or forward without the necessity of reversing or stopping the engine.

Numerous attempts have been made to construct devices for varying the pitch angle of propeller blades while a propeller is in rotation. However, these devices, and especially the ones for use with small outboard motors, have serious defects. Either the parts have not been sufficiently strong to withstand the high speed of the motor or the complexity of the devices renders them extremely expensive and difficult to repair. In addition, few such devices have been developed which may be sold as an accessory unit and which may be readily assembled on the conventional outboard motor.

It is therefore a primary object of the present invention to provide an accessory propeller device of the character described which obviates the defects hereinbefore mentioned.

Another object of this invention is to provide a device of the character described which has a minimum of working parts and which is strong enough to withstand the high speed and constant shock loads of the propeller driven motor.

Still another object of this invention is to provide a device of the character described which is comparatively inexpensive and efficient in operation and which may be readily manufactured in quantity.

Yet another object of this invention is to provide a device of the character described which may be sold as an accessory unit for attachment to conventional propeller driven motors.

With these and other objects and advantages in view, which will become more apparent during the course of the following description, the invention consists in the features and combinations hereinafter set forth.

In order to make the invention more fully understood, preferred embodiments thereof have According to the present invention, the.

14 Claims. (Cl. 170160.36)

been made the subject of illustration in the accompanying drawings in which:

Figure 1 is a side elevation of the lower end of a power leg of a conventional outboard motor showing the device of the present invention associated therewith;

Figure 2 is a vertical section of the device of Figure 1 taken on the line 2--2 thereof;

- Figure 3 is a vertical section of the device of this invention taken along the line 3--3 of Figure 2;

Figure 4 is a horizontal section of the device of this invention taken along the line 4-4 of Figure 3; and l a Figure 5 is a plan view of the inner sleeve of the present device with the pins engaged in the respective slots therein.

In its briefest form, the present invention embodies a propeller pitch changing device having a drive shaft with an inner sleeve mounted for rotation therewith. An outer sleeve is positioned about the inner sleeve for rotation and relative longitudinal movement with the inner sleeve. A plurality of propeller blades each having a base are pivotally mounted on said outer sleeve, and

means are provided on said blades which extend through the outer sleeve to engage the inner sleeve and retain said blades for rotation with the sleeves. An eccentric pin is fixed in the base of each blade so as to extend through an enlarged aperture in the outer sleeve. Recesses are provided in the inner sleeve for engaging the eccentric pins and preventing their movement longitudinally of the inner sleeve when the outer sleeve is moved longitudinally relative to the inner sleeve. Means are further provided for limiting the relative movement of the sleeves and for controlling this movement as desired. Further details of the structure of the device of this invention will be apparent from the following description.

Referring to the drawings, Figure 1 shows the lower end In of a power leg of a conventional outboard motor. The major parts of this power leg as shown are a guard II for the propeller, a reinforcing and balancing fin l2, a cooling water intake I3 and a gear box 14. Part of a drive shaft [5 is shown extending from the rear of the gear box at right angles thereto. This drive shaft is journalled in the power leg through sealed bearings so as to protect the inner working parts of the power leg. Of course, all of these parts of the motor as shown are treated to resist corrosion in fresh or salt water.

The device of the present invention is secured 3 to the drive shaft l5 to form a propeller hub, generally designated as 26. A plurality of propeller blades 2 I, are retained in position about the hub 2|] in such manner that they may be .pivoted upon their longitudinal axis. A pitch angle actuating means, generally designated by the numeral 22, will be described in more detail later.

As shown in Figures 2 and 3, the device of this invention is mounted upon a drive shaft which, as shown, is tapered, but may be straight or any other shape. This device has an inner sleeve having a tapered inner bore 3i. In mounting the device upon the tapered drive shaft, the inner sleeve is placed over the tapered shaft and secured in position by nut 32 which is screwed down on the screw threaded end 33 of the drive shaft. A soft metal shear pin 34 ensures unitary rotation of the hub and drive shaft. It will be noted that the outer surface 35 of the sleeve 30 is of cylindrical, non-tapered form. A plurality of slots 36 are spaced circumferentially about the inner sleeve in'the outer surface thereof. These slots are counterbored or milled inwardly of the surface 35 at 31 to form an outer shelf or ledge 38. At the rear end of the sleeve 30 is an external circumferentialfiange 33.

Concentrically mounted on the inner sleeve is an outer sleeve 40 which is designed to rotate in unison with the inner sleeve and the drive shaft, but at the same time to move longitudinally relative to the inner sleeve. This outer sleeve has a plurality of round turrets 4| having bores 42 therein for axial alignment with the slots 36 of the inner sleeve. A propeller blade 2|, provided with a shankor base 5|, is seated in each a bore 42. Though the base of each propeller blade fits snugly within each bore, the base is designed to rotate within the bore during the varying of the pitch of the propeller. In order to retain each blade within the hub defined by Q the concentric sleeves 30 and 46, a retaining pin- 52 is provided. This pin 52 extends through a slot in the outer sleeve and up into a bore 53 centrally aligned in the base of each propeller blade. This retaining pin is locked for axial rotation with the propeller blade by a locking pin 54 which passes through the base of the blade and the retaining pin at right angles to the latter. Holes 55 are provided in the turret 4| for inserting and removing the locking pin 54.

Toward the rear of the sleeve 40 is a counterbore which leaves a space between the inner and outer sleeve for the positioning, of a compression spring 6| inwardly of the flange 39 in the inner sleeve. This spring tends to force the outer sleeve longitudinally forward of the inner sleeve, the forward position being the position in which the normal pitch angle of the blades is blades are assembled in the hub. Of course, in placing the retaining pin in the slot, the long axis of the pin is made parallel with thelong axis of the slot so that it will fit down into the milled counterbore 31 and then the pin is turned to retain it in position. Also fixed in the base of the propeller blade is an eccentric actuating pin 51 which extends through an arcuate slot 58in the bottom of the bore 42 of the outer sleeve 46. This pin is set in a recess 59 in the side of the 5 inner sleeve 30. The recess 59 is of approximately the same width as thediameter of the pin 51 but has considerable radial depth for a purpose to be pointed out later.

Figure 5 shows the inner sleeve with slot 36 10 and recesses 59 therein. The dotted lines show the extent of the bore 31 within the slot 36. Sections of actuating pins 51 are shown in position in the recesses 59, and a section of a retaining pin 52 is shown in the slot 36 with its 15 extended head engaged below the ledge 38.

In operation the pitch angle of the blades is changed by altering the relative longitudinal positioning of the outer sleeve with respect to the inner sleeve. The outer sleeve is forced against go the action of the compression spring 6| by the action of the bell crank mechanism 22 as shown in Figure 1. This mechanism includes a lever 10 which is attached to a bell crank 1L. Of course means, notshown, may also be provided 25 for locking the lever in any desired position. The bell crank is pivoted at 12 to the power leg and has a roller 13 for engaging the bevelededge bearing ring 65. r

In normal operating position the bell crank 0 mechanism 22 does not bear against the ring 65. However, when it is desired to alter the pitch of the blades the lever 10 is pulled forward at its upper end to engage roller 13 with the front face of the bearing ring 65, thus sliding the outer sleeve along the inner sleeve against the action of compression spring 6|. Obviously, when the outer sleeve is moved, each propeller blade and base is moved longitudinally of the inner sleeve a corresponding distance. Since the slot 36 in the innersleeve is of considerable length the retaining pin may move to the extreme forward and rear limits of movement of the outer sleeve and still serve to retain the propeller blade. However, since the eccentric pivot pin 51 of each 45 propeller blade base is anchored against longitudinal movement in the recess 53 thebase of the propeller blade is forced to rotate about its central axis through the retaining pin 52. As the base 5| is rotated about its axis, the pin 51 will '50 move radially along the long axis of the recess 59 which is of sufiicient depth to accommodate the extreme movement of the pin. Thearcuate slot 58 in the bottom of the bore 42 of the outer sleeve permits the outer sleeve to travel longi- 55 tudinally of the pin 51 as the latter moves radially in the recess 59. A better understanding of this operation will be ascfi ftained by reference to Figure 4 wherein the pins 51 are positioned such that .the'pitch angle of the blades would be 60 in the intermediate position. The dot and dash lines which cross each other indicate the extreme {pitch of the blade from one limit to the other. it {should be noted that when 'the bla'des are in the normal forward driving position the roller 13 does not contact the ring-65. the blades being held in this position. by the'action of the spring 6,1. The plate. 62 determines the limit of the forward. driving pitch angle.

.It will be understood that various changes may be made, such as in the size, shape and arrangement of parts or by the substitution of equivalents without departing from the spirit ofthis invention. Consequently, the invention is not limited to the formal uses shown, except to the extent indicated in the appended claims,

s men which are to be interpreted as broadly as the state oi the art will permit;

I claim: i. In a propeller pitch changing device of the character described. a drive shaft, an inner sleeve mounted for rotation therewith, an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a pluralityof propeller blades each having a base pivotally' mounted on said outer-sleeve, means on said blades extending through said outer sleeve "to-engage the inner sleeve andretain said blades for rotation with said sleevesyan eccentric pin fixedi'n the base of each blade, 'and'extending through an enlargedaperture inthe outer sleeve, recesses in the inner sleeve for engaging said pins and preventing their movement longitudinally of the inner sleeve when the outersleeve is moved longitudinally relative to the inner sleeve, and means for controlling the relative movement of the two sleeves.

2. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve mounted for rotation therewith, an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of propeller blades each having a base pivotally mounted on said outer sleeve, means on said blades extending through said outer sleeve to engage the inner sleeve and retain said blades for rotation with said sleeves, an eccentric pin fixed in the base of each blade, said outer sleeve having an aperture therein through which the eccentricpin extends, said aperture being large enough to permit substantial arcuate movement of the pin about the longitudinal axis of the blade, recesses in the inner sleeve for engaging said pins and preventing their movement longitudinally of the inner sleeve when the outer sleeve is moved longitudinally relative to the inner sleeve, andmeans for controlling the rela tive movement of the two sleeves.

3. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve mounted for rotation therewith, an outer sleeve positionedabout said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of propeller blades each having a base pivotally mounted on said outer sleeve, a retaining pin extending from each base through the outer sleeve, said retaining pins engaging theinner sleeve to'retain said blades for movement with said inner sleeve; an eccentric pin fixed in the base of each blade, and extending through an enlargedaperture in the outer sleeve, recesses in the inner sleeve for engaging said pins and preventing their movement lon- *gitudinally of the inner sleeve when the outer sleeve is moved longitudinally relative to the inner sleeve, and means for controlling the relative movement of the two sleeves.

4. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve mounted for rotation therewith, a plurality of slots in the outer surface of said inner sleeve, a retaining ledge formed in said slot; an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of propeller blades each having a base pivotally mounted on said outer sleeve, a retainingpin extending from each base through the outer sleeve and extending through the slot in the inner sleeve to be engaged below the ledge in the slot and retain said bladeson saia shelves, an eccentric pin fixed in the base sleeve mounted for rotation therewith, an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of bores in said outer sleeve, propeller blades each having a base io'r positioning in one of said bores, means'on said blades extending through said outer sleeve to engagethe inner sleeve and retain said blades for rotation with said sleeves, an eccentric pin fixed in the base of each blade, and extending through an enlarged aperture in the outer sleeve, recesses in the inner sleeve for engaging said eccentric pins and preventing their movement longitudinally of the inner sleeve when the outer sleeve is moved longitudinally relative to the inner sleeve, and means for controlling the relative movement of the two sleeves.

6. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve mounted for rotation therewith, a plurality of slots in the outer surface of said inner sleeve, a retaining ledge formed in said slot, an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of bores in said outer sleeve, propeller blades each having a base for positioning in one of said bores, a retaining pin extending from each base through the outer sleeve and extending through the slot in the inner sleeve to be e rTg'aged below the ledge in the slot and retain said blades on said shelves, an eccentric pin fixed in the base of each blade and extending through an enlarged aperture in the outer sleeve, recesses in the inner sleeve for engagingsaid eccentric pins and preventing their movement longitudinally of the inner sleeve when the outer sleeve is moved longitudinally relative to the inner sleeve, and means for controlling the relative movement of the two sleeves. 7. In a propeller pitch changing device of th character described, a drive shaft, an inner sleeve mounted for rotation therewith, an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of propeller blades each having a base pivotally mounted on said outer sleeve, a retaining pin extending from each base through the outer sleeve, said retaining pins engaging the inner sleeve to retain said blades for movement with said inner sleeve, an eccentric pin hired in the base of each blade, said outer sleeve having an aperture therein through which the eccentric pin extends, said aperture being large enough to aeeaseo sleeve, a retaining ledge formed in said slot, an outer sleeve mounted for limited longitudinal movement with the inner sleeve, a plurality of bores in said outer sleeve for radial alignment with the slots in the inner sleeve, propeller blades each having a -base for positioning in one of said bores, a retaining pin extending from each base through the inner sleeve, said retaining pin being secured, for unitary movement with the propeller blade, said retaining pin further having means for engaging the retaining ledge in the slot in the inner sleeve to retain said propeller blades on said sleeves, said slot in said inner sleeve being sufficiently long to permit limited movement of the retaining pin longitudinally of the inner sleeve, a pivot pin mounted eccentrically in the base of each propeller blade,

a slot in reach bore of the outer sleeve for permitting the outer sleeve to move longitudinally of said pivot pins, recesses in the inner sleeve for engaging the pivot pins, and means for controlling the relative movement of said sleeves.

9. In a propeller pitch changing device of the character described, a tapered drive shaft, an inner sleeve having a tapered bore and mounted on said shaft for rotation therewith, said sleeve having a plurality of radially disposed slots in the outer surface thereof, each of said slots having an inner enlarged counterbore defining an outer ledge, an outer sleeve mounted concentrically on said inner sleeve for limited longitudinal movement therewith, a plurality of bores through said outer sleeve in general radial alignment with the slots in the inner sleeve, a plurality of propeller blades each having a base for positioning in one of said bores, a retaining pin extending axially from each propeller blade base and through the inner sleeve, a locking pin securing said retaining pin to said propeller base so that the base and retaining pin will rotate in unison, said retaining pin having a head which is enlarged along one axis for fitting in the slot in the inner sleeve and engaging beneath the ledge formed by said counterbore in order to retain said propeller blades on said sleeve, said slot and counterbore in said inner sleeve being sufficiently long to permit limited movement of the retaining pin longitudinally of the inner sleeve, a pivot pin mounted eccentrically in the base of each propeller blade, an arcuate slot in each bore of said outer sleeves for permitting the outer sleeve to move longitudinally of said pivot pins,

recesses on said inner sleeve for engaging the pivot pins and preventing their movement longitudinally of the inner sleeve, and means for moving said sleeves longitudinally of one another and retaining them in a desired relatively position.

10. In a propeller pitch changing device of the character described, a tapered drive shaft, an inner sleeve having a tapered bore and mounted on said shaft for rotation therewith, said sleeve having a plurality of radially disposed slots in the outer surface thereof, each of said slots having an inner enlarged counterbore defining an outer ledge, an outer sleeve mounted concentrically on said inner sleeve for limited longitudinal movement therewith, a plurality of bores through said outer sleeve in general radial alignment with the slots in the inner sleeve, a plurality of propeller blades each having a base for positioning in one of said bores, a retaining pin extending axially from each propeller blade base and through the inner sleeve, a locking pin securing said retaining pin to said propeller base so 10 a pivot pin mounted eccentrically in the base of each propeller blade, an arcuate slot in each bore of said outer sleeves for permitting the outer sleeve to move longitudinally of said pivot pins, recesses on said inner sleeve for engaging the ,pivot pins and preventing their movement longi- ,;tudinally of the inner sleeve, 9. plate on the rear of the outer sleeve for limiting its forward movementpa'nd a compression spring positioned be- ;tween's'aid'innerand outer sleeves for urging said outer 'sleeve forward to a normal pitch angle.

11. In a propeller pitch changing device of the character described, a tapered drive shaft, an inner sleeve having a tapered bore and mounted on said shaft for rotation therewith, said sleeve having a plurality of radially disposed slots in the outer surface thereof, each of said slots having an inner enlarged counterbore defining an outer ledge, an outer sleeve mounted concentrically on said inner sleeve for limited longitudinal movement therewith, a plurality of bores through said outer sleeve in general radial alignment with the slots in the inner sleeve, a plurality of propeller blades each having a base for positioning in one of said bores, a retaining pin ex- 5 tending axially from each propeller blade base and through the inner sleeve, a locking pin securing said retaining pin to said propeller base so that the base and retaining pin will rotate in unison, said retaining pin having a head which is enlarged along one axis for fitting in the slot in the inner sleeve and engaging beneath the ledge formed by said counterbore in order to retain said propeller blades on said sleeve, said slot and counterbore in said inner sleeve being sufiiciently long to permit limited movementof the retaining pin longitudinally of the inner sleeve, a pivot pin mounted eccentrically inthe base of each propeller blade, an arcuate slot in each bore of said outer sleeves for permitting the outer sleeve to move longitudinally of said pivot pins, recesses on said inner sleeve for engaging the pivot pins and preventing their movement longitudinally of the inner sleeve, a plate on the rear of the outer sleeve for limiting its forward movement, a compression spring positioned between said inner and outer sleeves for urging said outer sleeve forward to a normal pitch angle, a ring against the forward end of the outer sleeve and overriding the inner sleeve,

00 and a bell crank mechanism for engagement with said ring for forcing said outer sleeve longitudinally of said inner sleeve against the action of said spring.

12. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve mounted for rotation therewith, said sleeve having slots in the outer surface thereof, each of said slots having an inner enlarged counterbore defining an outer ledge, an outer sleeve positioned about said inner sleeve for rotation and relative longitudinal movement therewith, a plurality of propeller blades each having a base pivotally mounted on said outer sleeve, a retaining pin extending from each base through the outer sleeve, 9. head on said retaining pin for fitting in the slot in the inner sleeve beneath said ledge formed by said counterbore, said head contacting opposed sides of the counterbore and the underside of the ledge to securely retain said propeller blades on said sleeves, an eccentric pin fixed in the base of each blade and extending through an enlarged aperture in the outer sleeve, recesses in the inner sleeve for engaging said pins and preventing their movement longitudinally of the inner sleeve when the outer sleeve is moved longitudinally relative to the inner sleeve, and means for controlling the relative movement of the two sleeves.

13. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve having a bore and mounted on said shaft for rotation therewith, said sleeve having slots in the outer surface thereof, each of said slots having an inner enlarged counterbore definng an outer ledge, an outer sleeve mounted concentrically on said inner sleeve for limited longitudinal movement therewith, a plurality of bores through said outer sleeve in general radial alignment with the slots in the inner sleeve, a plurality of propeller blades each having a base for positioning in one of said bores, a retaining pin extending axially from each propeller blade base and through the inner sleeve, said retaining pin having a head which is enlarged along one axis for fitting in the slot in the inner sleeve and engaging beneath the ledge formed by said counterbore in order to retain said propeller blades on said sleeve, said slot and counterbore in said inner sleeve being ,sufiiciently long to permit limited movement of the retaining pin longitudinally of the inner sleeve, a pivot pin mounted eccentrically in the base of each propeller blade, an aperture in each bore of said outer sleeve for permitting the outer sleeve to move longitudinally of said pivot pins, recesses on said inner sleeve for engaging the pivot pins and preventing their movement longitudinally of the inner sleeve, and means for moving said sleeves longitudinally of one another.

14. In a propeller pitch changing device of the character described, a drive shaft, an inner sleeve having a bore and mounted on said shaft for rotation therewith. said sleeve having slots in the outer surface thereof, each of said slots having an inner enlarged counterbore defining an outer ledge, an outer sleeve mounted concentrically on said inner sleeve for limited longitudinal movement therewith, a plurality of bores through said outer sleeve in general radial alignment with the slots in the inner sleeve, a plurality of propeller blades each having a base for positioning in one of said bores, a retaining pin extending axially from each propeller blade base and through the inner sleeve, said retaining pin having a head which is enlarged along one axis for fitting in the slot in the inner sleeve and engaging beneath the ledge formed by said counterbore in order to retain said propeller blades on said sleeve, said slot and counterbore in said inner sleeve being sufliciently long to permit limited movement of the retaining pin longitudinally of the inner sleeve, a pivot pin mounted eccentrically in the base of each propeller blade, an aperture in each bore of said outer sleeve for permitting the outer sleeve to move longitudinally of said pivot pins, recesses on said inner sleeve for engaging the pivot pins and preventing their movement longitudinally of the inner sleeve, means for urging said outer sleeve forward to a normal pitch angle, means for limiting the forward movement of the outer sleeve, and a ring against the forward end of the outer sleeve and over-riding the inner sleeve and a bell crank mechanism for engagement with said ring for forcing said outer sleeve longitudinally of said inner sleeve against the action of said spring.

HERMAN GANSERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 667,223 Keller Feb. 5,1901 1,496,496 Silick June 3, 1925 1,737,523 Smith Nov. 26, 1929 1,891,384 Gillis et al Dec, 20, 1932 FOREIGN PATENTS Number Country Date 189,821 France Apr. 7, 1888 346,522 France Jan. 27, 1905 343,777 Great Britain Feb. 26, 1931 

